Vehicles such as an automobile are equipped with wiper apparatuses for wiping off rain water adhering to a windshield (front windshield) and splashes from front vehicles for the purpose of ensuring the driver's field of view in cases of rainy weather. A wiper apparatus includes a wiper arm which is controlled to oscillate by a wiper driving device. A wiper blade which comes into contact with a windshield is attached to the end of the wiper arm. A pivot shaft which is driven to rotate by a wiper motor is arranged on the body side of the vehicle. The wiper arm is attached to the pivot shaft, and oscillates at a preset control angle according to rotation of the motor.
In attaching a wiper arm to a pivot shaft, the wiper arm has conventionally been fixed to the pivot shaft with an arm position set so that the wiper arm operates at a predetermined control angle. Since the position of the wiper arm is designed on the basis of theoretical values calculated in advance, the position of the wiper blade varies vehicle by vehicle due to dimensional errors, rigidity, and the like of the wiper arm, the wiper blade, and the body. In particular, when an assembly of a wiper arm and a wiper blade (hereinafter, abbreviated as arm & blade) is mounted on the vehicle body, the wiper arm is attached by using a predetermined jig because the assembly is susceptible to deflection of the arm or the blade. For example, in a conventional wiper attaching operation, the arm is initially stopped at a lower retracted position. The wiper arm is then fastened with a nut and mounted on the pivot shaft by using a dedicated jig so that the end of the wiper blade falls within a prescribed range.